Genetic diversity and taxonomy: a reassessment of species designation in tuatara (Sphenodon: Reptilia)

Abstract

The identification of species boundaries for allopatric populations is important for setting conservation priorities and can affect conservation management decisions. Tuatara (Sphenodon) are the only living members of the reptile order Sphenodontia and are restricted to islands around New Zealand that are free of introduced mammals. We present new data of microsatellite DNA diversity and substantially increased mtDNA sequence for all 26 sampled tuatara populations. We also re-evaluate existing allozyme data for those populations, and together use them to examine the taxonomic status of those populations. Although one could interpret the data to indicate different taxonomic designations, we conclude that, contrary to current taxonomy, Sphenodon is best described as a single species that contains distinctive and important geographic variants. We also examine amounts of genetic variation within populations and discuss the implications of these findings for the conservation management of this iconic taxon.

Conservation status of New Zealand reptiles, 2009

“…comm. ); (2) unpublished results of R Hitchmough and the thesis of Nielsen (2008) for geckos; (3) the review of tuatara genetics and systematics by Hay et al (2010) (which reduced tuatara to a single species); and (4) the list of marine reptiles published by Gill (1997), with the addition of one more recently described sea snake species with a specimen recorded from New Zealand (Heatwole et al 2005). We used the suggested common names of Jewell (2008) for some recently discovered or recently distinguished species that did not already have appropriate and well-established common names, but we did not change wellestablished common names.…”

Jaw Adductor Muscles across Lepidosaurs: A Reappraisal

“…The Lepidosauria, encompassing Rhynchocephalia (represented by two extant species of tuatara, or one according to Hay et al, 2009) and Squamata (nearly 7200 species of lizards, amphisbaenians and snakes), includes a diverse and speciose living clade of reptiles (Vitt and Caldwell, 2008;Conrad, 2008;Evans, 2008;Uetz, 2010Uetz, , 2011. For such a diverse group, the problems of maintaining a consistent-and homology-based muscle nomenclature are exacerbated.…”

The First Cytogenetic Map of the Tuatara, <i>Sphenodon punctatus</i>

“…Until recently, 2 allopatric species of tuatara were recognized: Sphenodon punctatus and Sphenodon guntheri , [Daugherty et al, 1990]. However, recent genetic analyses by Hay et al [2009] indicate that tuatara should be regarded as a single species (S. punctatus) , with 3 distinct genetic/geographic groups.…”